You now need to edit appropriately the Courier-IMAP configuration files
installed in ${SYSCONFDIR}/.

Pay particular attention to the details in imapd.cnf, and read ssl(8) if
necessary. You MUST set the CN in imapd.cnf to the hostname by which
your IMAP server is accessed, or else clients will complain. When this
is done, you can use the 'mkimapdcert' script to automatically generate
a server certificate, which is installed into /etc/ssl/imapd.pem
